On Fri, 31 Aug 2007 01:53:01 -0400, Miguel Pacheco
<escorpion1955@YAHOO.COM> wrote:

>That 'spiral tube' is called a bourdon tube. Widely used in industry, of
>course, to measure psi and even as a switch.........just an FYI. Cheers.

Yup, thanks for the info.
BTW, I have here 3 air pressure meters, one pen-type and two dial-type,
with only one of the latter with that so-called "bourdon tube".
The other two are of the spring-loaded piston-cylinder type, not safe for
fuel because the seal relies on the sealing of a moving plastic piston,
which isn't safe inherently and also might be attacked by the fuel.
I opened the bourdon tube one up and the pressure path is all metal
(except for the o-rings) and can handle 100psi, so I guess it might be OK,
once I find an adapter.